Crane-hinge for muffle-furnace doors



G. W. LINDSAY.

CRANE HINGE FOR MUFFLE FURNACE DOORS.

APPLICATION FILED SEPT- 23, I918.

1,346,903 Patented J uly 20, 1920.

Z 2 I l /9 g /7 z/ 20 l /J I i 1 v 2.9 3/) 3 7 28 mgwmh A I UNITED STATES PATE ro Ic- GEORGE w. LINDsAY, or DENVER, COLORADO, AssIGNoR To DENVE EIRE CLAY T COMPANY, OF DENVER, coLoRADo, CORPORATION OF- DELAWARE.

CRANE-HINGE FOB. MUFFLE-FURNAGE DOORS.

' Application fil ed September To all whom it may concern: 7

Be it known that I, GEORGE W. LrNDsAY, a citizen of the United States, residing at the city and county of Denver and State of Colorado, have invented certain new and useful Improvements in Crane-Hinges for Mufile-Furnace Doors; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it'appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form a part of this specification.

This invention relates to muffle furnaces and the object thereof is the provision of a hinge for the door which will support the door in closed, position and will also hold it in open position at any angle and permit of its being readily swung into closed position without lifting the door.

Briefly the invention comprises a crane hinged to the furnace, the door being swiveled to the outer end thereof. In one form the crane is jointed at the middle, the joint being so constructed that it will prevent a dead center. In the drawings:

Figure 1 shows a front elevation of a portion of a muffle furnace with one form of the invention applied thereto.

Fig. 2 is a section approximately on the line 22 of Fig. 1, the furnace wall being broken away to show the door in plan.

Fig. 3 is a front elevation showing another form. Fig. 4 is a section approximately on the line 44 of Fig. 3 with the door in plan as in Fig. 2.

Fig. 5. is a section of a hinge as indicated by line 5-5 of Fig. 3.

The furnace 10 of Fig. 1 is provided with a door 12 to which is connected a support 14 having a handle 15 and secured to the door through the medium of extensions 16. The support 14 is provided with an upstanding stem 17 for connection to the crane 18 which is hingedly connected to the furnace at719. A sleeve 20 on the outer end of the crane fits about the stem 17 which is retained in position by a nut 21 adjustable to position the door.

In Fig. 2 the door is shown in open position by dotted lines, the dashed line a indi- Specification of Letters Patent. Patented J ly 20 1920 23, 1918. Serial No. 255,328.

of the crane 18 when the door is operated by the handle 15.

In Figs. 3'and 4 a'handle 25 is mounted on the door 112 by means of supports 26 from which an upstanding stem 27 extends. A crane composed of an arm 28 hingedly connected with the furnace 110 at 29 and an arm 30 hinged to the arm 28 at 31 supports the door by means of a sleeve 32 on the outer end of the arm 30 which engages the stem 27, the latter being retained by nut 33 adjustable to position the door. The part of the hinge 31 on arm 30'is provided with an extension 34 which overlaps the arm 28 when the furnace door is in closed position center.

By grasping the handle 25 the door 112,

as soon'as it is withdrawn from its seat in the furnace, may be moved almost directly sidewise into the position shown in dotted lines in Fig. 4, the right hand edge of the door taking the path indicated by the finely dotted line b. I

It will thus be seen that the door may be set at any angle desired when not in closed position'and that it may always be readily swung into any position. By using the jointed crane of Figs-3 and 4, it is unnecessary that the door describe a large arc in moving from one position to another. In fact, it may be merely-shifted laterally short distance.

I claim: c

1. A mounting for muffle furnace doors comprising in combination with a furnace and its door, a crane hingedly mountedat tween the other end of the crane and the.

door and a handle adjacent said swivel connection the crane portion of said swivel connection being positioned above the door, whereby the door may be swung out beneath the crane.

3. In combination with a furnace and its door, a crane hingedly connected at one end with the furnace and having a swivel connection with the door at the other end, said cranecomprising two arms hinged together the crane portion of said swivel connection being positioned above the door, whereby the door may be swung out beneath the crane. 4. In combination with a furnace and its door, a crane hingedly connected at one-end With the furnace and having a swivel connection with the door at the other end, said crane comprising two arms hinged together,

said hinge having means thereon to limit its motion and prevent the formation of a dead center the crane portion of said swivel connection and said hinge being positioned above the door, whereby the door may be swung out beneath the crane.

5. In combination with a furnace and its door, a crane hingedly connected at one end with the outer wall of the furnace and having a swivel connection with the outer wall of the door at the other end, said crane com- 3 prising two arms hinged together, and a handle adjacent said swivel connection the crane portionof saidswivel connection and said hinge being positioned above the door, whereby the door may be swung out beneath th cran T imony whereofI aflix my signature.

I In test GEORGE W. LI D AY; 

